You all know oscilloscopes from old science fiction movies: Those strange screens showing waves. Well, those machines have a practical use in electronics for measuring all kinds of alternating power. Usualy a 'scope uses a CRT (modern ones are digital, of course), and were incredible expensive for an amateur until maybe 20 years ago. But there is of course the Dieselpunk-solution: Make your own, mechanical Oscilloscope! The manual is from "Modern Mechanix", issue November 1936, which you can find here: http://blog.modernmechanix.com/2009/09/17/seeing-sound-with-a-home-...
It seemed to me quite easy to make my own oszilloscope with that manual. I've just replaced the clockwork with an electric motor, and the flashlight and lenses with a laser from a laser pointer. (Which made it a bit easier to build.)
And here you see (and hear) it working:
More pictures and detailed information you can find at the forum of the "Narrow Bandwidth Television Association" (Where I'm a member): http://www.taswegian.com/NBTV/forum/viewtopic.php?t=1500
Very clever! I honestly think there's even a market for such a thing for DJs and dance halls. As an electrical engineer it's probably limited in scientific value, but cool factor is through the roof. Tie that thing into a Therien now, Herr Doktor!
Yep, I remember when my Dad got his first Oscilloscope. He was like a kid with a new toy. Of course in those days electronics still used tubes. Also, at work, he used Assembly Code to program computers.